Since the spinal cord is the connecting pathway for most mechanisms of the body's various organs, injury to it can cause dysfunction in almost all biological systems. Spinal cord injuries are calmitous, not only physically but psychosocially and financially. Approximately 10,000 to 12,000 new spinal cord injuries occur each year in the United States. In spite of advances in methods and appliances designed for the protection of the cord in spinal injuries, there are still too many patients able to move their extremities shortly after the accident who suffer irrepairable damage to the spinal cord through attempts that are made to move the patient from the scene of the accident to the hospital.
There are a number of techniques for the transport or removal of an accident victim suspected of having a spinal injury. For example, some of these techniques are described in Fire Service First Aid Practices, Fifth Edition, Oklahoma State University; Krueger et al., "Transportation and First Aid in Patients with Spinal Cord Injuries", New York State Journal of Medicine, Vol. 63, pp. 682-690, March 1963. In general, the techniques involve providing appropriate support for the body before any lifting takes place. An example of such a technique concerns the use of a spine board to which the victim is strapped (see the Fire Services First Aid Practices publication). Reference is also made to U.S. Pat. Nos. 4,034,748 (Winner) and 3,737,923 (Prolo).
As explained hereinbelow, the present invention utilizes a flexible bladder which is constructed so that it can be made rigid, and thereby conform to the shape of the victim, under the control of the user. In a specific embodiment, the bladder is filled with a plurality of so-called "microballoons" or spheres which form a rigid mass when the pressure within the bladder is less than ambient. A number of patents disclose devices of this type. One example is U.S. Pat. No. 3,212,497 (Dickinson) which discloses a moldable temporary splint comprising a flexible bag containing particles which consolidate into a rigid mass when the bag is evacuated. Two patents which employ this technique in restraining or immobilizing a patient are U.S. Pat. No. 3,762,404 (Sakita) and U.S. Pat. No. 3,745,998 (Rose). The Sakita patent discloses a "positioning aid" for immobilizing a part of the body of a medical patient which comprises an airtight bag filled with beads which form a rigid mass when the vacuum in the bag is destroyed by opening a self-closing valve. In certain embodiments, the bag is used to support the torso. The Rose patent discloses a somewhat similar vacuum-formed "support structure and immobilization device." A further patent of interest is U.S. Pat. No. 4,024,861 (Vincent) which discloses a spinal support in the form of an inflatable bag to which the victim is secured by straps so as to immobilize his spine during movement. Reference is also made to U.S. Pat. No. 3,415,243 (Sheldon) which discloses a surgical cast that includes a plurality of reagents which are reactive when intermixed to form a hardenable cast material and which are imbedded in surgical gauze. Rupture of an encapsulation for one of the reagents enables mixing of the reagents.